houdini Crowd

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inspired by the talented ball project, I'm using houdini to made a crowd, the idea is basically to generate forms from a bunch of people, Gears for example.
I have made it work but maybe there are another solutions to make it better , because I'm running in optimization problems; the simulation is too slow , having just 200 peoples, each frame of the simulation takes about one hour to compute!!!

what Im doing is the following:

first I use 13 different Models , import from a FBX file that has point cache of the geometry, this cache consist urn 6 different cycles (the cycles were made in maya then I exported to FBX with cache), then in the chop network, I trim them, getting 6 animations from each file, I use the Cycle chop to make a cycle of the animation, then I use the Shift Chop to vary the cycle for each person in the simulation, and finally I use a stretch chop to change the velocity.

for placing ,moving and handling the decisions of which model use, cycle, velocity cycle, Hue shift etc. I use a copy shop to copy each model on each particle using stamp functions to communicate the decisions made in pop to the model's chop operator. there is wen the tinges get very slow.

ca some one helpmeet to optimize this cooking proses?,or ther is another way to make th same result?.
I think ha the problem lays in the chop network, because each model have about 2000 points, so it have 2000 curves in the chop network that most be cycled , offseted and streched but maybe is another ting going on!

the .hipnc file is about 150mb , Im trying to stor in a site so you can have a look in that.


Thank you so much!!

the Video is here
http://www.youtube.com/watch?v=Bp3y8L7mX-U [youtube.com]



ok Finally the files!!!


http://clientes.clusterstudio.com/public/ [clientes.clusterstudio.com]


one for hnc one for the cache

Attachments:
HoudiniMassive.mov (3.5 MB)

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A couple of months ago I made a crowd system in Houdini for use in a commercial. And I used almost the exact approach as you've done on yours as far as I can see and remember.

I used FBX-imported geometry with geometry cache from Maya. Offset of speed and animation in in CHOP's and copied them onto a bunch of particles with stamping.

We used two different models for each instance depending on the distance from camera. The reading and modifying of all the CHOP curves is as far as I've noticed the big time consumer, which we solved by just having the instances of the models in the front with the full-res model. As you point out since its three curves per point, the point number is really crucial to that approach.

One thing which might help, although I'm not sure. Is to save out the geometry caches to *.chan-files. Perhaps those are faster for Houidini to read.

Regarding the file size of your scene, I suspect that the imported geometries and caches are baked into the scene file which perhaps isn't necessary. Try unlocking your file nodes in your FBX-geometry and in your CHOP network.

Sadly I don't really remember if there were any magic tricks to getting it to run faster. But one hour seems a bit extreme. We had close to 15.000 instances and it never took longer than 5 minutes to compute the geometry as far as I can remember. But our geometry was probably not near as intense.

We were thinking of using some kind of low-res geometry as a deformer and similar just to decrease the point count in CHOP's but in the end we've made it with just brute force.

Here's the finished film by the way if you're interested:
http://www.youtube.com/watch?v=FzKgURH82_E [youtube.com]
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It looks very promising btw.
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thank you so much, I'm going to try it!!!
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xtimmyx
A couple of months ago I made a crowd system in Houdini for use in a commercial. And I used almost the exact approach as you've done on yours as far as I can see and remember.

I used FBX-imported geometry with geometry cache from Maya. Offset of speed and animation in in CHOP's and copied them onto a bunch of particles with stamping.

We used two different models for each instance depending on the distance from camera. The reading and modifying of all the CHOP curves is as far as I've noticed the big time consumer, which we solved by just having the instances of the models in the front with the full-res model. As you point out since its three curves per point, the point number is really crucial to that approach.

One thing which might help, although I'm not sure. Is to save out the geometry caches to *.chan-files. Perhaps those are faster for Houidini to read.

Regarding the file size of your scene, I suspect that the imported geometries and caches are baked into the scene file which perhaps isn't necessary. Try unlocking your file nodes in your FBX-geometry and in your CHOP network.

Sadly I don't really remember if there were any magic tricks to getting it to run faster. But one hour seems a bit extreme. We had close to 15.000 instances and it never took longer than 5 minutes to compute the geometry as far as I can remember. But our geometry was probably not near as intense.

We were thinking of using some kind of low-res geometry as a deformer and similar just to decrease the point count in CHOP's but in the end we've made it with just brute force.

Here's the finished film by the way if you're interested:
http://www.youtube.com/watch?v=FzKgURH82_E [youtube.com]

Hi, I am doing some crowd too, I I'like to ask for a little help, can you tell me how did you use CHOPS with instancing to offset the speed and animation?

Thanks
https://vimeo.com/user2163076 [vimeo.com]
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mzigaib
Hi, I am doing some crowd too, I I'like to ask for a little help, can you tell me how did you use CHOPS with instancing to offset the speed and animation?

Thanks

Hi, well I was using geometry caches which are read in CHOP's. Those in turn were connected to Shift and Stretch CHOP's if I remember correctly. These were using copy stamping to get the offset different on the Shift CHOP.

On the Stretch CHOP which controls the speed of the animation I used the speed of the particle divided by the size of the individual so that a small hen would move faster than a big one running at the same speed.

Hope it makes some sense to you.
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Yes it does, thanks you very much.
https://vimeo.com/user2163076 [vimeo.com]
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